The molds used in horizontal continuous casting apparatus normally provide a smooth, substantially axially uninterrupted interior surface of a cross-sectional shape corresponding to that of the desired cast product, such as, for example, round bar or square billet. Such surface wears in the normal course of use, requiring periodic replacement, and is also from time to time subject to accidental marring, thus requiring unscheduled replacement.
In order to provide both reasonable strength and good heat conductivity for solidifying molten metal to form the outer shell of the product being cast, continuous casting molds are typically made of a relatively expensive copper alloy, such as beryllium-copper, for example. Relatively complex flanges are required at either end of the mold, for mating such mold with the water jacket or similar cooling apparatus which surrounds the mold exterior, as well as for mating such mold both with the refractory materials interposed between the mold and the tundish and slide gate on the one end, and with the primary aftercooler or similar apparatus on the other end.
Heretofore, these molds have been of unitary construction with the required flanges, thus necessitating the replacement of both the actual casting portion of the mold and both flanges each time that either normal wear or accidental damage to the casting surface so indicates, even though the flanges as such are typically neither worn nor damaged. Plainly, the replacement of the flanges is, in and of itself, needlessly expensive. Replacement is, however, made even more economically disadvantageous by such unitary construction, for, under the circumstances, the attainment of such construction requires that each mold, whether original or replacement, be either forged into blank from billet and then finish-machined, or machined in its entirety from a single large piece of alloy. Either way, allocated capital cost, labor cost, and materials cost combine to adversely affect the cost effectiveness and justification of the continuous casting process and apparatus as a whole.